[R] Partition a vector into select groups with fixed length

[Rui Barradas]

Hello,

The following function will do it.
It uses a standard cumsum trick to create a break vector f.
And predicts special cases (n = 0 or n = 1).

breakVec <- function(x, n = 5){
   if(n < 1) stop(paste("Illegal value n:", n))
   if(n == 1){
     f = ""
   }else{
     f <- c(1, rep(0, n - 1))
     f <- rep(f, length.out = length(x))
     f <- cumsum(f)
   }
   split(x, f)
}

breakVec(LETTERS)
breakVec(LETTERS, 4)
breakVec(LETTERS, 1)
breakVec(LETTERS, -1)


Hope this helps,

Rui Barradas

Às 19:01 de 18/08/19, Christofer Bogaso escreveu:
> Hi,
> 
> Let say I have a vector as below
> 
> Vec = LETTERS
> 
> Now I want to break this vector into groups of the same length of 5.
> 
> So,
> 1st group consists - "A" "B" "C" "D" "E"
> 2nd group - "F" "G" "H" "I" "J"
> 
> and so on..
> last group will consist only the leftover elements
> 
> I have a very large initial vector, so looking for some efficient way
> to achieve the same. Any pointer will be highly appreciated.
> 
> Thanks for your time.
> 
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